1. Field of the Invention
The present invention relates to a heat exchanger which is available for an evaporator for an automotive air conditioner or the like.
2. Description of the Related Art
For this sort of heat exchanger, there is known a heat exchanger that includes a flat fluid communication chamber and a flat fin accommodated in the fluid communication chamber and having a configuration corresponding to the chamber. As shown in FIG. 1, the fin 101 has two opposing ends 101a, 101b provided with openings 102, 103, respectively. The heat exchanger is constructed so as to allow fluid to flow from the opening 102 toward the opening 103.
In the heat exchanger of this sort, there is a tendency that the fluid flows toward the center of the fin 101 in large quantity while the fluid flows toward the periphery of the fin 101 in small quantity since the flowing resistance of fluid in the direction X is smaller that in the direction Y. As a result, the heat exchanger has problems of a greater pressure loss and a smaller heat exchanger amount.
In order to solve these problems about the heat exchanger, Japanese Patent Application Laid-open No. 2000-18848 discloses a countermeasure as shown in FIG. 2. The fin 101 is provided, on both ends thereof, with openings 102, 103 each having auxiliary openings 104, 105 extending from the openings 102, 103 in the direction Y. Alternatively, the openings 102, 103 are modified to be either elliptical or rhomboidal thereby expanding in the direction Y.
Nevertheless, there still remains a problem that only small quantity of fluid flows into both ends of the fin 101, so that heat exchange is hardly carried out in these areas of the fin 101.